Dust cap



' 1,619,710 March 1927' w. F. DURYEA DUST CAP Filed DeC. 28. 1925 WITNESSES v ZZ- INVEN'I'OR 777/ ianoi'flur ea BY pv/zllf, L1 M ATTORNEYS Patented Mar. 1, 1927.

'UNlTED STATES WILLIAM F. DURYEA, 0F HACKENSACK, NEW JERSEY:

DUST CAP.

Application filed December 28, 1925. Serial No. 77,909.

The present invention relates to improve ments in dust caps for automobile tire valves. It is an object of the invention to provide a dust cap which may be quickly ap plied to, or removed from the stem of a conventional tire valve without the necessity of screwing or unscrewing the dust cap.

More specifically, an object of the invention is to provide a dust cap which is frictionally fitted over the valve stem, and which is equipped with means for snugly engaging the stem to prevent the accidental displacement of-the cap under the vibrations and shocks which maybe imparted to the automobile wheel.

Further objects of the invention are to provide a dust cap which will be of simple, practical construction, which will be rugged and durable, which may be manufactured with comparative economy, and which is well suited to meet the requirements of practical use.

With the above noted and other objects in view, the invention consists in certain novel features of construction and combinations and arrangements of parts, as will be more fully hereinafter set forth and pointed out in the claim. The invention may be more fully understood from the following description in connection with the accompanying drawings, wherein Fig. 1 is a longitudinal sectional view through a dust cap embodying the present invention.-

Fig. 2 is a transverse sectional view on the line 8-8 of Fig. 1.

Fig. 3 is a plan view of the blank from which the spring metal stem gripping memher is formed.

lliig. 1 is a perspective view of the spring member removed from the dust cap.

The present invention is more particularly concerned with the provision of the main dust cap 14:, and the means for effecting frictional engagement of this dust cap with a valve stem, (not shown) whereby the tedious operations of screwing or unscrewing the valve cap are eliminated.

The dust cap 20 is of cylindrical construction, open at its lower end, and closed at its top end. The internal diameter of the cap is materially greater than the external diameter of the valve stem to which it is to be applied, and to efiect frictional engagement of the cap with the stem, ll house within the cap a stem engaging element designated by the reference numeral 16. Fig. 3 shows the member 16 after it has been blanked out of a suitable sheet of spring metal. The blank includes a relatively wide metallic strip or band 17, from one edge of which project a plurality of integral parallel fingers 18;

The number of fingers which form part of the element 16 is subject to considerable variation, but 1 have found four to be the most suitable number, especially where the device is to be employed in connection with a conventional valve stem, having two flat sides.

The next operation in forming member 16 is to curve the strip 17 into approximately circular shape so that it defines a split collar from which the. fingers 18 depend. Fingers 18 are then flared outwardly at their lower ends, and the element 16 inserted in the dust cap 20 until the ring 17 abuts against the closed end of the cap. The device in this position is shown in Fig. 1, wherein it will be noted that the fingers 18 are forced inwardly so that only their free ends contact with the inner wall of the cap. The operation of inserting member 16 into the cap, necessarily includes the circumferential contraction of the ring 17 c The expanding tendency of the ring 17 serves to hold the unit 16 securely in place against longitudinal movement within the cap, and the fingers 18 are bent or flattened by the valve stem as the cap is applied.

It is to be noted that one advantage of utilizing four of the spring fingers 18, is the fact that the cap does not have to be properly centered or rotatably adjusted relative to the stem before its insertion. If the fingers 18 should happen to engage the corners of the stem defined by the flat and rounded sides thereof, the fingers will be more firmly compressed, and the frictional engagement of the cap will be increased. lin any event the inherent resiliency of the fingers is such that when the cap is in place, the frictional engagementof the fingers effectively prevents dislocation of the capdue to vibrations of the car.

Obviously this type of dust cap may be applied and removed with great facility and expedition. lit is a very simple matter to ad ust the spring member 16 in order to predetermine both the frictional engagement of the ring 17 with the cap, and the frictional engagement of the fingers 18 with the valve stem. By efi'ecting relative separation of the ends of the ring 17 before the unit 16 is inserted, greater force will be required to contract the ring sufiiciently to permit insertion of the latter, and consequently a firmer gripping engagement will be had between the ring and the cap. To increase the tension on the fingers 18 it is merely necessary to accentuate the flare of these fingers,thereby increasing their inherent resistance to a flattening action.

The valve stems are made in two standard sizes, and the dust cap may be used with either sized valve.

It is formed with a plurality of integral inwardly presented longitudinally extended ribs 21 on its interior, these ribs alternating with grooves 22. The ribs and grooves extend the full length of the cap, and when the member 16 is inserted, the fingers may be selectively used for gripping either a large diameter, or small diameter valve. The device has been shown in the drawings as assembled for use with the smaller stem, and it will be noted that the fingers 18 rest against the ribs 21. By thesimple expedient of rotatably shifting the entire unit 18 in the cap, the fingers will move into the grooves 22, and the device will be of proper size to snugly embrace the larger valve stem. By providing the two sets of bearing surfaces for the fingers 18, I may manufacture the caps in one standard size, and predetermine by the assembling operation, their suitability for either size valve stem.

Various changes and alterations might be made in the general form and arrangement of parts described without departing from the invention. Hence I do not wish to limit myself to the details set forth, but shall consider myself at liberty to make such changes and alterations as fairly fall within the spirit and scope of the appended claim.

, I claim:

The combination with a cylindrical dust cap having a plurality of longitudinally extending alternate ribs and grooves at its in terior, of a member disposed Within the dust cap, including a split spring ring portion frictionally engaging the ribs, and a plural ity of spring fingers integral with the ring portion adapted for selective disposition either against the ribs or in the grooves,

whereby the fingers may snugly engage a plurality'of sizes of valve stems.

WILLIAM F. DURYEA. 

